forked from Minki/linux
7b93640502
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1022 lines
24 KiB
C
1022 lines
24 KiB
C
/*
|
|
* net/sched/sch_generic.c Generic packet scheduler routines.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*
|
|
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
|
|
* Jamal Hadi Salim, <hadi@cyberus.ca> 990601
|
|
* - Ingress support
|
|
*/
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/string.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/rtnetlink.h>
|
|
#include <linux/init.h>
|
|
#include <linux/rcupdate.h>
|
|
#include <linux/list.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/if_vlan.h>
|
|
#include <net/sch_generic.h>
|
|
#include <net/pkt_sched.h>
|
|
#include <net/dst.h>
|
|
|
|
/* Qdisc to use by default */
|
|
const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops;
|
|
EXPORT_SYMBOL(default_qdisc_ops);
|
|
|
|
/* Main transmission queue. */
|
|
|
|
/* Modifications to data participating in scheduling must be protected with
|
|
* qdisc_lock(qdisc) spinlock.
|
|
*
|
|
* The idea is the following:
|
|
* - enqueue, dequeue are serialized via qdisc root lock
|
|
* - ingress filtering is also serialized via qdisc root lock
|
|
* - updates to tree and tree walking are only done under the rtnl mutex.
|
|
*/
|
|
|
|
static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
|
|
{
|
|
q->gso_skb = skb;
|
|
q->qstats.requeues++;
|
|
qdisc_qstats_backlog_inc(q, skb);
|
|
q->q.qlen++; /* it's still part of the queue */
|
|
__netif_schedule(q);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void try_bulk_dequeue_skb(struct Qdisc *q,
|
|
struct sk_buff *skb,
|
|
const struct netdev_queue *txq,
|
|
int *packets)
|
|
{
|
|
int bytelimit = qdisc_avail_bulklimit(txq) - skb->len;
|
|
|
|
while (bytelimit > 0) {
|
|
struct sk_buff *nskb = q->dequeue(q);
|
|
|
|
if (!nskb)
|
|
break;
|
|
|
|
bytelimit -= nskb->len; /* covers GSO len */
|
|
skb->next = nskb;
|
|
skb = nskb;
|
|
(*packets)++; /* GSO counts as one pkt */
|
|
}
|
|
skb->next = NULL;
|
|
}
|
|
|
|
/* This variant of try_bulk_dequeue_skb() makes sure
|
|
* all skbs in the chain are for the same txq
|
|
*/
|
|
static void try_bulk_dequeue_skb_slow(struct Qdisc *q,
|
|
struct sk_buff *skb,
|
|
int *packets)
|
|
{
|
|
int mapping = skb_get_queue_mapping(skb);
|
|
struct sk_buff *nskb;
|
|
int cnt = 0;
|
|
|
|
do {
|
|
nskb = q->dequeue(q);
|
|
if (!nskb)
|
|
break;
|
|
if (unlikely(skb_get_queue_mapping(nskb) != mapping)) {
|
|
q->skb_bad_txq = nskb;
|
|
qdisc_qstats_backlog_inc(q, nskb);
|
|
q->q.qlen++;
|
|
break;
|
|
}
|
|
skb->next = nskb;
|
|
skb = nskb;
|
|
} while (++cnt < 8);
|
|
(*packets) += cnt;
|
|
skb->next = NULL;
|
|
}
|
|
|
|
/* Note that dequeue_skb can possibly return a SKB list (via skb->next).
|
|
* A requeued skb (via q->gso_skb) can also be a SKB list.
|
|
*/
|
|
static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
|
|
int *packets)
|
|
{
|
|
struct sk_buff *skb = q->gso_skb;
|
|
const struct netdev_queue *txq = q->dev_queue;
|
|
|
|
*packets = 1;
|
|
if (unlikely(skb)) {
|
|
/* skb in gso_skb were already validated */
|
|
*validate = false;
|
|
/* check the reason of requeuing without tx lock first */
|
|
txq = skb_get_tx_queue(txq->dev, skb);
|
|
if (!netif_xmit_frozen_or_stopped(txq)) {
|
|
q->gso_skb = NULL;
|
|
qdisc_qstats_backlog_dec(q, skb);
|
|
q->q.qlen--;
|
|
} else
|
|
skb = NULL;
|
|
return skb;
|
|
}
|
|
*validate = true;
|
|
skb = q->skb_bad_txq;
|
|
if (unlikely(skb)) {
|
|
/* check the reason of requeuing without tx lock first */
|
|
txq = skb_get_tx_queue(txq->dev, skb);
|
|
if (!netif_xmit_frozen_or_stopped(txq)) {
|
|
q->skb_bad_txq = NULL;
|
|
qdisc_qstats_backlog_dec(q, skb);
|
|
q->q.qlen--;
|
|
goto bulk;
|
|
}
|
|
return NULL;
|
|
}
|
|
if (!(q->flags & TCQ_F_ONETXQUEUE) ||
|
|
!netif_xmit_frozen_or_stopped(txq))
|
|
skb = q->dequeue(q);
|
|
if (skb) {
|
|
bulk:
|
|
if (qdisc_may_bulk(q))
|
|
try_bulk_dequeue_skb(q, skb, txq, packets);
|
|
else
|
|
try_bulk_dequeue_skb_slow(q, skb, packets);
|
|
}
|
|
return skb;
|
|
}
|
|
|
|
/*
|
|
* Transmit possibly several skbs, and handle the return status as
|
|
* required. Owning running seqcount bit guarantees that
|
|
* only one CPU can execute this function.
|
|
*
|
|
* Returns to the caller:
|
|
* 0 - queue is empty or throttled.
|
|
* >0 - queue is not empty.
|
|
*/
|
|
int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
|
|
struct net_device *dev, struct netdev_queue *txq,
|
|
spinlock_t *root_lock, bool validate)
|
|
{
|
|
int ret = NETDEV_TX_BUSY;
|
|
|
|
/* And release qdisc */
|
|
spin_unlock(root_lock);
|
|
|
|
/* Note that we validate skb (GSO, checksum, ...) outside of locks */
|
|
if (validate)
|
|
skb = validate_xmit_skb_list(skb, dev);
|
|
|
|
if (likely(skb)) {
|
|
HARD_TX_LOCK(dev, txq, smp_processor_id());
|
|
if (!netif_xmit_frozen_or_stopped(txq))
|
|
skb = dev_hard_start_xmit(skb, dev, txq, &ret);
|
|
|
|
HARD_TX_UNLOCK(dev, txq);
|
|
} else {
|
|
spin_lock(root_lock);
|
|
return qdisc_qlen(q);
|
|
}
|
|
spin_lock(root_lock);
|
|
|
|
if (dev_xmit_complete(ret)) {
|
|
/* Driver sent out skb successfully or skb was consumed */
|
|
ret = qdisc_qlen(q);
|
|
} else {
|
|
/* Driver returned NETDEV_TX_BUSY - requeue skb */
|
|
if (unlikely(ret != NETDEV_TX_BUSY))
|
|
net_warn_ratelimited("BUG %s code %d qlen %d\n",
|
|
dev->name, ret, q->q.qlen);
|
|
|
|
ret = dev_requeue_skb(skb, q);
|
|
}
|
|
|
|
if (ret && netif_xmit_frozen_or_stopped(txq))
|
|
ret = 0;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* NOTE: Called under qdisc_lock(q) with locally disabled BH.
|
|
*
|
|
* running seqcount guarantees only one CPU can process
|
|
* this qdisc at a time. qdisc_lock(q) serializes queue accesses for
|
|
* this queue.
|
|
*
|
|
* netif_tx_lock serializes accesses to device driver.
|
|
*
|
|
* qdisc_lock(q) and netif_tx_lock are mutually exclusive,
|
|
* if one is grabbed, another must be free.
|
|
*
|
|
* Note, that this procedure can be called by a watchdog timer
|
|
*
|
|
* Returns to the caller:
|
|
* 0 - queue is empty or throttled.
|
|
* >0 - queue is not empty.
|
|
*
|
|
*/
|
|
static inline int qdisc_restart(struct Qdisc *q, int *packets)
|
|
{
|
|
struct netdev_queue *txq;
|
|
struct net_device *dev;
|
|
spinlock_t *root_lock;
|
|
struct sk_buff *skb;
|
|
bool validate;
|
|
|
|
/* Dequeue packet */
|
|
skb = dequeue_skb(q, &validate, packets);
|
|
if (unlikely(!skb))
|
|
return 0;
|
|
|
|
root_lock = qdisc_lock(q);
|
|
dev = qdisc_dev(q);
|
|
txq = skb_get_tx_queue(dev, skb);
|
|
|
|
return sch_direct_xmit(skb, q, dev, txq, root_lock, validate);
|
|
}
|
|
|
|
void __qdisc_run(struct Qdisc *q)
|
|
{
|
|
int quota = dev_tx_weight;
|
|
int packets;
|
|
|
|
while (qdisc_restart(q, &packets)) {
|
|
/*
|
|
* Ordered by possible occurrence: Postpone processing if
|
|
* 1. we've exceeded packet quota
|
|
* 2. another process needs the CPU;
|
|
*/
|
|
quota -= packets;
|
|
if (quota <= 0 || need_resched()) {
|
|
__netif_schedule(q);
|
|
break;
|
|
}
|
|
}
|
|
|
|
qdisc_run_end(q);
|
|
}
|
|
|
|
unsigned long dev_trans_start(struct net_device *dev)
|
|
{
|
|
unsigned long val, res;
|
|
unsigned int i;
|
|
|
|
if (is_vlan_dev(dev))
|
|
dev = vlan_dev_real_dev(dev);
|
|
res = netdev_get_tx_queue(dev, 0)->trans_start;
|
|
for (i = 1; i < dev->num_tx_queues; i++) {
|
|
val = netdev_get_tx_queue(dev, i)->trans_start;
|
|
if (val && time_after(val, res))
|
|
res = val;
|
|
}
|
|
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL(dev_trans_start);
|
|
|
|
static void dev_watchdog(unsigned long arg)
|
|
{
|
|
struct net_device *dev = (struct net_device *)arg;
|
|
|
|
netif_tx_lock(dev);
|
|
if (!qdisc_tx_is_noop(dev)) {
|
|
if (netif_device_present(dev) &&
|
|
netif_running(dev) &&
|
|
netif_carrier_ok(dev)) {
|
|
int some_queue_timedout = 0;
|
|
unsigned int i;
|
|
unsigned long trans_start;
|
|
|
|
for (i = 0; i < dev->num_tx_queues; i++) {
|
|
struct netdev_queue *txq;
|
|
|
|
txq = netdev_get_tx_queue(dev, i);
|
|
trans_start = txq->trans_start;
|
|
if (netif_xmit_stopped(txq) &&
|
|
time_after(jiffies, (trans_start +
|
|
dev->watchdog_timeo))) {
|
|
some_queue_timedout = 1;
|
|
txq->trans_timeout++;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (some_queue_timedout) {
|
|
WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n",
|
|
dev->name, netdev_drivername(dev), i);
|
|
dev->netdev_ops->ndo_tx_timeout(dev);
|
|
}
|
|
if (!mod_timer(&dev->watchdog_timer,
|
|
round_jiffies(jiffies +
|
|
dev->watchdog_timeo)))
|
|
dev_hold(dev);
|
|
}
|
|
}
|
|
netif_tx_unlock(dev);
|
|
|
|
dev_put(dev);
|
|
}
|
|
|
|
void __netdev_watchdog_up(struct net_device *dev)
|
|
{
|
|
if (dev->netdev_ops->ndo_tx_timeout) {
|
|
if (dev->watchdog_timeo <= 0)
|
|
dev->watchdog_timeo = 5*HZ;
|
|
if (!mod_timer(&dev->watchdog_timer,
|
|
round_jiffies(jiffies + dev->watchdog_timeo)))
|
|
dev_hold(dev);
|
|
}
|
|
}
|
|
|
|
static void dev_watchdog_up(struct net_device *dev)
|
|
{
|
|
__netdev_watchdog_up(dev);
|
|
}
|
|
|
|
static void dev_watchdog_down(struct net_device *dev)
|
|
{
|
|
netif_tx_lock_bh(dev);
|
|
if (del_timer(&dev->watchdog_timer))
|
|
dev_put(dev);
|
|
netif_tx_unlock_bh(dev);
|
|
}
|
|
|
|
/**
|
|
* netif_carrier_on - set carrier
|
|
* @dev: network device
|
|
*
|
|
* Device has detected that carrier.
|
|
*/
|
|
void netif_carrier_on(struct net_device *dev)
|
|
{
|
|
if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
|
|
if (dev->reg_state == NETREG_UNINITIALIZED)
|
|
return;
|
|
atomic_inc(&dev->carrier_changes);
|
|
linkwatch_fire_event(dev);
|
|
if (netif_running(dev))
|
|
__netdev_watchdog_up(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(netif_carrier_on);
|
|
|
|
/**
|
|
* netif_carrier_off - clear carrier
|
|
* @dev: network device
|
|
*
|
|
* Device has detected loss of carrier.
|
|
*/
|
|
void netif_carrier_off(struct net_device *dev)
|
|
{
|
|
if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
|
|
if (dev->reg_state == NETREG_UNINITIALIZED)
|
|
return;
|
|
atomic_inc(&dev->carrier_changes);
|
|
linkwatch_fire_event(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(netif_carrier_off);
|
|
|
|
/* "NOOP" scheduler: the best scheduler, recommended for all interfaces
|
|
under all circumstances. It is difficult to invent anything faster or
|
|
cheaper.
|
|
*/
|
|
|
|
static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
|
|
struct sk_buff **to_free)
|
|
{
|
|
__qdisc_drop(skb, to_free);
|
|
return NET_XMIT_CN;
|
|
}
|
|
|
|
static struct sk_buff *noop_dequeue(struct Qdisc *qdisc)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
struct Qdisc_ops noop_qdisc_ops __read_mostly = {
|
|
.id = "noop",
|
|
.priv_size = 0,
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.peek = noop_dequeue,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static struct netdev_queue noop_netdev_queue = {
|
|
.qdisc = &noop_qdisc,
|
|
.qdisc_sleeping = &noop_qdisc,
|
|
};
|
|
|
|
struct Qdisc noop_qdisc = {
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.flags = TCQ_F_BUILTIN,
|
|
.ops = &noop_qdisc_ops,
|
|
.q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
|
|
.dev_queue = &noop_netdev_queue,
|
|
.running = SEQCNT_ZERO(noop_qdisc.running),
|
|
.busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
|
|
};
|
|
EXPORT_SYMBOL(noop_qdisc);
|
|
|
|
static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt)
|
|
{
|
|
/* register_qdisc() assigns a default of noop_enqueue if unset,
|
|
* but __dev_queue_xmit() treats noqueue only as such
|
|
* if this is NULL - so clear it here. */
|
|
qdisc->enqueue = NULL;
|
|
return 0;
|
|
}
|
|
|
|
struct Qdisc_ops noqueue_qdisc_ops __read_mostly = {
|
|
.id = "noqueue",
|
|
.priv_size = 0,
|
|
.init = noqueue_init,
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.peek = noop_dequeue,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static const u8 prio2band[TC_PRIO_MAX + 1] = {
|
|
1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1
|
|
};
|
|
|
|
/* 3-band FIFO queue: old style, but should be a bit faster than
|
|
generic prio+fifo combination.
|
|
*/
|
|
|
|
#define PFIFO_FAST_BANDS 3
|
|
|
|
/*
|
|
* Private data for a pfifo_fast scheduler containing:
|
|
* - queues for the three band
|
|
* - bitmap indicating which of the bands contain skbs
|
|
*/
|
|
struct pfifo_fast_priv {
|
|
u32 bitmap;
|
|
struct qdisc_skb_head q[PFIFO_FAST_BANDS];
|
|
};
|
|
|
|
/*
|
|
* Convert a bitmap to the first band number where an skb is queued, where:
|
|
* bitmap=0 means there are no skbs on any band.
|
|
* bitmap=1 means there is an skb on band 0.
|
|
* bitmap=7 means there are skbs on all 3 bands, etc.
|
|
*/
|
|
static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0};
|
|
|
|
static inline struct qdisc_skb_head *band2list(struct pfifo_fast_priv *priv,
|
|
int band)
|
|
{
|
|
return priv->q + band;
|
|
}
|
|
|
|
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
|
|
struct sk_buff **to_free)
|
|
{
|
|
if (qdisc->q.qlen < qdisc_dev(qdisc)->tx_queue_len) {
|
|
int band = prio2band[skb->priority & TC_PRIO_MAX];
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
struct qdisc_skb_head *list = band2list(priv, band);
|
|
|
|
priv->bitmap |= (1 << band);
|
|
qdisc->q.qlen++;
|
|
return __qdisc_enqueue_tail(skb, qdisc, list);
|
|
}
|
|
|
|
return qdisc_drop(skb, qdisc, to_free);
|
|
}
|
|
|
|
static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
int band = bitmap2band[priv->bitmap];
|
|
|
|
if (likely(band >= 0)) {
|
|
struct qdisc_skb_head *qh = band2list(priv, band);
|
|
struct sk_buff *skb = __qdisc_dequeue_head(qh);
|
|
|
|
if (likely(skb != NULL)) {
|
|
qdisc_qstats_backlog_dec(qdisc, skb);
|
|
qdisc_bstats_update(qdisc, skb);
|
|
}
|
|
|
|
qdisc->q.qlen--;
|
|
if (qh->qlen == 0)
|
|
priv->bitmap &= ~(1 << band);
|
|
|
|
return skb;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
int band = bitmap2band[priv->bitmap];
|
|
|
|
if (band >= 0) {
|
|
struct qdisc_skb_head *qh = band2list(priv, band);
|
|
|
|
return qh->head;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void pfifo_fast_reset(struct Qdisc *qdisc)
|
|
{
|
|
int prio;
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
|
|
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
|
|
__qdisc_reset_queue(band2list(priv, prio));
|
|
|
|
priv->bitmap = 0;
|
|
qdisc->qstats.backlog = 0;
|
|
qdisc->q.qlen = 0;
|
|
}
|
|
|
|
static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb)
|
|
{
|
|
struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS };
|
|
|
|
memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1);
|
|
if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
|
|
goto nla_put_failure;
|
|
return skb->len;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
|
|
static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
|
|
{
|
|
int prio;
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
|
|
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
|
|
qdisc_skb_head_init(band2list(priv, prio));
|
|
|
|
/* Can by-pass the queue discipline */
|
|
qdisc->flags |= TCQ_F_CAN_BYPASS;
|
|
return 0;
|
|
}
|
|
|
|
struct Qdisc_ops pfifo_fast_ops __read_mostly = {
|
|
.id = "pfifo_fast",
|
|
.priv_size = sizeof(struct pfifo_fast_priv),
|
|
.enqueue = pfifo_fast_enqueue,
|
|
.dequeue = pfifo_fast_dequeue,
|
|
.peek = pfifo_fast_peek,
|
|
.init = pfifo_fast_init,
|
|
.reset = pfifo_fast_reset,
|
|
.dump = pfifo_fast_dump,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
EXPORT_SYMBOL(pfifo_fast_ops);
|
|
|
|
static struct lock_class_key qdisc_tx_busylock;
|
|
static struct lock_class_key qdisc_running_key;
|
|
|
|
struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
|
|
const struct Qdisc_ops *ops)
|
|
{
|
|
void *p;
|
|
struct Qdisc *sch;
|
|
unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size;
|
|
int err = -ENOBUFS;
|
|
struct net_device *dev = dev_queue->dev;
|
|
|
|
p = kzalloc_node(size, GFP_KERNEL,
|
|
netdev_queue_numa_node_read(dev_queue));
|
|
|
|
if (!p)
|
|
goto errout;
|
|
sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
|
|
/* if we got non aligned memory, ask more and do alignment ourself */
|
|
if (sch != p) {
|
|
kfree(p);
|
|
p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL,
|
|
netdev_queue_numa_node_read(dev_queue));
|
|
if (!p)
|
|
goto errout;
|
|
sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
|
|
sch->padded = (char *) sch - (char *) p;
|
|
}
|
|
qdisc_skb_head_init(&sch->q);
|
|
spin_lock_init(&sch->q.lock);
|
|
|
|
spin_lock_init(&sch->busylock);
|
|
lockdep_set_class(&sch->busylock,
|
|
dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
|
|
|
|
seqcount_init(&sch->running);
|
|
lockdep_set_class(&sch->running,
|
|
dev->qdisc_running_key ?: &qdisc_running_key);
|
|
|
|
sch->ops = ops;
|
|
sch->enqueue = ops->enqueue;
|
|
sch->dequeue = ops->dequeue;
|
|
sch->dev_queue = dev_queue;
|
|
dev_hold(dev);
|
|
refcount_set(&sch->refcnt, 1);
|
|
|
|
return sch;
|
|
errout:
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
|
|
const struct Qdisc_ops *ops,
|
|
unsigned int parentid)
|
|
{
|
|
struct Qdisc *sch;
|
|
|
|
if (!try_module_get(ops->owner))
|
|
return NULL;
|
|
|
|
sch = qdisc_alloc(dev_queue, ops);
|
|
if (IS_ERR(sch)) {
|
|
module_put(ops->owner);
|
|
return NULL;
|
|
}
|
|
sch->parent = parentid;
|
|
|
|
if (!ops->init || ops->init(sch, NULL) == 0)
|
|
return sch;
|
|
|
|
qdisc_destroy(sch);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(qdisc_create_dflt);
|
|
|
|
/* Under qdisc_lock(qdisc) and BH! */
|
|
|
|
void qdisc_reset(struct Qdisc *qdisc)
|
|
{
|
|
const struct Qdisc_ops *ops = qdisc->ops;
|
|
|
|
if (ops->reset)
|
|
ops->reset(qdisc);
|
|
|
|
kfree_skb(qdisc->skb_bad_txq);
|
|
qdisc->skb_bad_txq = NULL;
|
|
|
|
if (qdisc->gso_skb) {
|
|
kfree_skb_list(qdisc->gso_skb);
|
|
qdisc->gso_skb = NULL;
|
|
}
|
|
qdisc->q.qlen = 0;
|
|
}
|
|
EXPORT_SYMBOL(qdisc_reset);
|
|
|
|
static void qdisc_rcu_free(struct rcu_head *head)
|
|
{
|
|
struct Qdisc *qdisc = container_of(head, struct Qdisc, rcu_head);
|
|
|
|
if (qdisc_is_percpu_stats(qdisc)) {
|
|
free_percpu(qdisc->cpu_bstats);
|
|
free_percpu(qdisc->cpu_qstats);
|
|
}
|
|
|
|
kfree((char *) qdisc - qdisc->padded);
|
|
}
|
|
|
|
void qdisc_destroy(struct Qdisc *qdisc)
|
|
{
|
|
const struct Qdisc_ops *ops = qdisc->ops;
|
|
|
|
if (qdisc->flags & TCQ_F_BUILTIN ||
|
|
!refcount_dec_and_test(&qdisc->refcnt))
|
|
return;
|
|
|
|
#ifdef CONFIG_NET_SCHED
|
|
qdisc_hash_del(qdisc);
|
|
|
|
qdisc_put_stab(rtnl_dereference(qdisc->stab));
|
|
#endif
|
|
gen_kill_estimator(&qdisc->rate_est);
|
|
if (ops->reset)
|
|
ops->reset(qdisc);
|
|
if (ops->destroy)
|
|
ops->destroy(qdisc);
|
|
|
|
module_put(ops->owner);
|
|
dev_put(qdisc_dev(qdisc));
|
|
|
|
kfree_skb_list(qdisc->gso_skb);
|
|
kfree_skb(qdisc->skb_bad_txq);
|
|
/*
|
|
* gen_estimator est_timer() might access qdisc->q.lock,
|
|
* wait a RCU grace period before freeing qdisc.
|
|
*/
|
|
call_rcu(&qdisc->rcu_head, qdisc_rcu_free);
|
|
}
|
|
EXPORT_SYMBOL(qdisc_destroy);
|
|
|
|
/* Attach toplevel qdisc to device queue. */
|
|
struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
|
|
struct Qdisc *qdisc)
|
|
{
|
|
struct Qdisc *oqdisc = dev_queue->qdisc_sleeping;
|
|
spinlock_t *root_lock;
|
|
|
|
root_lock = qdisc_lock(oqdisc);
|
|
spin_lock_bh(root_lock);
|
|
|
|
/* Prune old scheduler */
|
|
if (oqdisc && refcount_read(&oqdisc->refcnt) <= 1)
|
|
qdisc_reset(oqdisc);
|
|
|
|
/* ... and graft new one */
|
|
if (qdisc == NULL)
|
|
qdisc = &noop_qdisc;
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc);
|
|
|
|
spin_unlock_bh(root_lock);
|
|
|
|
return oqdisc;
|
|
}
|
|
EXPORT_SYMBOL(dev_graft_qdisc);
|
|
|
|
static void attach_one_default_qdisc(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_unused)
|
|
{
|
|
struct Qdisc *qdisc;
|
|
const struct Qdisc_ops *ops = default_qdisc_ops;
|
|
|
|
if (dev->priv_flags & IFF_NO_QUEUE)
|
|
ops = &noqueue_qdisc_ops;
|
|
|
|
qdisc = qdisc_create_dflt(dev_queue, ops, TC_H_ROOT);
|
|
if (!qdisc) {
|
|
netdev_info(dev, "activation failed\n");
|
|
return;
|
|
}
|
|
if (!netif_is_multiqueue(dev))
|
|
qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
}
|
|
|
|
static void attach_default_qdiscs(struct net_device *dev)
|
|
{
|
|
struct netdev_queue *txq;
|
|
struct Qdisc *qdisc;
|
|
|
|
txq = netdev_get_tx_queue(dev, 0);
|
|
|
|
if (!netif_is_multiqueue(dev) ||
|
|
dev->priv_flags & IFF_NO_QUEUE) {
|
|
netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
|
|
dev->qdisc = txq->qdisc_sleeping;
|
|
refcount_inc(&dev->qdisc->refcnt);
|
|
} else {
|
|
qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT);
|
|
if (qdisc) {
|
|
dev->qdisc = qdisc;
|
|
qdisc->ops->attach(qdisc);
|
|
}
|
|
}
|
|
#ifdef CONFIG_NET_SCHED
|
|
if (dev->qdisc != &noop_qdisc)
|
|
qdisc_hash_add(dev->qdisc, false);
|
|
#endif
|
|
}
|
|
|
|
static void transition_one_qdisc(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_need_watchdog)
|
|
{
|
|
struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping;
|
|
int *need_watchdog_p = _need_watchdog;
|
|
|
|
if (!(new_qdisc->flags & TCQ_F_BUILTIN))
|
|
clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state);
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, new_qdisc);
|
|
if (need_watchdog_p) {
|
|
dev_queue->trans_start = 0;
|
|
*need_watchdog_p = 1;
|
|
}
|
|
}
|
|
|
|
void dev_activate(struct net_device *dev)
|
|
{
|
|
int need_watchdog;
|
|
|
|
/* No queueing discipline is attached to device;
|
|
* create default one for devices, which need queueing
|
|
* and noqueue_qdisc for virtual interfaces
|
|
*/
|
|
|
|
if (dev->qdisc == &noop_qdisc)
|
|
attach_default_qdiscs(dev);
|
|
|
|
if (!netif_carrier_ok(dev))
|
|
/* Delay activation until next carrier-on event */
|
|
return;
|
|
|
|
need_watchdog = 0;
|
|
netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog);
|
|
if (dev_ingress_queue(dev))
|
|
transition_one_qdisc(dev, dev_ingress_queue(dev), NULL);
|
|
|
|
if (need_watchdog) {
|
|
netif_trans_update(dev);
|
|
dev_watchdog_up(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(dev_activate);
|
|
|
|
static void dev_deactivate_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc_default)
|
|
{
|
|
struct Qdisc *qdisc_default = _qdisc_default;
|
|
struct Qdisc *qdisc;
|
|
|
|
qdisc = rtnl_dereference(dev_queue->qdisc);
|
|
if (qdisc) {
|
|
spin_lock_bh(qdisc_lock(qdisc));
|
|
|
|
if (!(qdisc->flags & TCQ_F_BUILTIN))
|
|
set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
|
|
qdisc_reset(qdisc);
|
|
|
|
spin_unlock_bh(qdisc_lock(qdisc));
|
|
}
|
|
}
|
|
|
|
static bool some_qdisc_is_busy(struct net_device *dev)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < dev->num_tx_queues; i++) {
|
|
struct netdev_queue *dev_queue;
|
|
spinlock_t *root_lock;
|
|
struct Qdisc *q;
|
|
int val;
|
|
|
|
dev_queue = netdev_get_tx_queue(dev, i);
|
|
q = dev_queue->qdisc_sleeping;
|
|
root_lock = qdisc_lock(q);
|
|
|
|
spin_lock_bh(root_lock);
|
|
|
|
val = (qdisc_is_running(q) ||
|
|
test_bit(__QDISC_STATE_SCHED, &q->state));
|
|
|
|
spin_unlock_bh(root_lock);
|
|
|
|
if (val)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* dev_deactivate_many - deactivate transmissions on several devices
|
|
* @head: list of devices to deactivate
|
|
*
|
|
* This function returns only when all outstanding transmissions
|
|
* have completed, unless all devices are in dismantle phase.
|
|
*/
|
|
void dev_deactivate_many(struct list_head *head)
|
|
{
|
|
struct net_device *dev;
|
|
bool sync_needed = false;
|
|
|
|
list_for_each_entry(dev, head, close_list) {
|
|
netdev_for_each_tx_queue(dev, dev_deactivate_queue,
|
|
&noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
dev_deactivate_queue(dev, dev_ingress_queue(dev),
|
|
&noop_qdisc);
|
|
|
|
dev_watchdog_down(dev);
|
|
sync_needed |= !dev->dismantle;
|
|
}
|
|
|
|
/* Wait for outstanding qdisc-less dev_queue_xmit calls.
|
|
* This is avoided if all devices are in dismantle phase :
|
|
* Caller will call synchronize_net() for us
|
|
*/
|
|
if (sync_needed)
|
|
synchronize_net();
|
|
|
|
/* Wait for outstanding qdisc_run calls. */
|
|
list_for_each_entry(dev, head, close_list)
|
|
while (some_qdisc_is_busy(dev))
|
|
yield();
|
|
}
|
|
|
|
void dev_deactivate(struct net_device *dev)
|
|
{
|
|
LIST_HEAD(single);
|
|
|
|
list_add(&dev->close_list, &single);
|
|
dev_deactivate_many(&single);
|
|
list_del(&single);
|
|
}
|
|
EXPORT_SYMBOL(dev_deactivate);
|
|
|
|
static void dev_init_scheduler_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc)
|
|
{
|
|
struct Qdisc *qdisc = _qdisc;
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc);
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
}
|
|
|
|
void dev_init_scheduler(struct net_device *dev)
|
|
{
|
|
dev->qdisc = &noop_qdisc;
|
|
netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
|
|
|
|
setup_timer(&dev->watchdog_timer, dev_watchdog, (unsigned long)dev);
|
|
}
|
|
|
|
static void shutdown_scheduler_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc_default)
|
|
{
|
|
struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
|
|
struct Qdisc *qdisc_default = _qdisc_default;
|
|
|
|
if (qdisc) {
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
|
|
dev_queue->qdisc_sleeping = qdisc_default;
|
|
|
|
qdisc_destroy(qdisc);
|
|
}
|
|
}
|
|
|
|
void dev_shutdown(struct net_device *dev)
|
|
{
|
|
netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
|
|
qdisc_destroy(dev->qdisc);
|
|
dev->qdisc = &noop_qdisc;
|
|
|
|
WARN_ON(timer_pending(&dev->watchdog_timer));
|
|
}
|
|
|
|
void psched_ratecfg_precompute(struct psched_ratecfg *r,
|
|
const struct tc_ratespec *conf,
|
|
u64 rate64)
|
|
{
|
|
memset(r, 0, sizeof(*r));
|
|
r->overhead = conf->overhead;
|
|
r->rate_bytes_ps = max_t(u64, conf->rate, rate64);
|
|
r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK);
|
|
r->mult = 1;
|
|
/*
|
|
* The deal here is to replace a divide by a reciprocal one
|
|
* in fast path (a reciprocal divide is a multiply and a shift)
|
|
*
|
|
* Normal formula would be :
|
|
* time_in_ns = (NSEC_PER_SEC * len) / rate_bps
|
|
*
|
|
* We compute mult/shift to use instead :
|
|
* time_in_ns = (len * mult) >> shift;
|
|
*
|
|
* We try to get the highest possible mult value for accuracy,
|
|
* but have to make sure no overflows will ever happen.
|
|
*/
|
|
if (r->rate_bytes_ps > 0) {
|
|
u64 factor = NSEC_PER_SEC;
|
|
|
|
for (;;) {
|
|
r->mult = div64_u64(factor, r->rate_bytes_ps);
|
|
if (r->mult & (1U << 31) || factor & (1ULL << 63))
|
|
break;
|
|
factor <<= 1;
|
|
r->shift++;
|
|
}
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(psched_ratecfg_precompute);
|